Spark plug



CII

Patented Aug. 6, 1929".

UNITED STATES HARVEY s. PRATT, or WHITING, IOWA.

SPARK PLUG.

Application led March 23, 1928. Serial No. 264,225.

The object et' this invention is to' provide a simple but eliicientmeans whereby the side electrode in a spark plug may be adjustedlongitudinally of the spark plug, as occasion may require, it being amatter ot' common knowledge that the side electrode must often beadjusted as above described, under many conditions, for instance, whenthe motor is pumping oil.

It is within the province of the disclosure to improve generally and toenhance the util.- ity of devices of that type to which the inventionappertains.

`With the above and other objects in view, which will appear as thedescription proceeds, the invention resides in the combination andarrangement of parts and in the details of construction hereinafterdescribed and claimed, it being understood that changes in the preciseembodiment of the invention herein disclosed, may be made within thescope of what is claimed, Without departing :from the spirit of theinvention.

In the accompanying drawings:

Figure 1 shows in longitudinal section, a spark plug constructed inaccordance with the invention;

Figure 2 is an elevation showing the carrier for the electrode;

Figure 3 is a bottom plan of the structure shown in Figure 2;

Figure 4 is a longitudinal section showing a modified form of theinvention.

Referring to Figures 1, 2 and 3, the numeral 1 designates the metal bodyof the spark plug, the body being provided with an internal shoulder 2.The numeral 3 designates a carrier or ring, made of metal and of conicalform, the carrier 3 having an upstanding annular liange 4 of cylindricalform. The carrier 3 is supplied at its lower end with a depending tongue5, in the outer surface of which a longitudinal groove G is formed. Thetongue 5 has transverse openings 7 spaced apart longitudinally of thetongue, the openings 7 communicating with the groove 6. A side electrodeis adapted to be mounted in any oi the openings. 7 the electrode 8provided at its outer end with a head 9 which is received in thelgrooveQGQ` Because the groove 6 is provided for the reception of thehead 9, the tongue 5`ean lieupfiat against the inner wall of the body 1of the spark plug, as shown in Figurei.. The 4carrier 3 rests on theshoulder 2, and the cylindrical.

iiange 4 lits within the chamber in the upper end oil the body 1, in away which will be understood readily when Figure 1 et the drawings isnoted.

The porcelain composition core oit the spark plug is designated by thenumeral 1() and carries the usual central electrode 11, which cooperateswith the side electrode 8. The core 10 is provided with an enlargement12 which has a superficial circumferential groove 14. About theenlargement 12, the enforcing collar 15 of metal extends. The collar 15has inwardly extended annular bead 16, which is U-sha-ped in crosssection, the bead 16 being received in the groove 14 of the core. Thecollar ,15 has an inclined flange 17 which engages the lower end of thecere 10, and bears on 'the carrier 3, the collar 15 being receivedwithin the annular flange 4 of the carrier 3 in the bushing 18 threadedinto the upper end of the body 1 of' the spark plug and bears on theupper end of the collar 15, only, the iiange 17 of the collar 15 bearingagainst the carrier 3, and there being no direct compression upon thecomposition core 10.

It is clear that the electrode 8 may be ad justed lengthwise of thespark plug, by mounting the electrode in any ofthe openings 7 of thetongue 5.

In Figure 4 of the drawings, parts hereinbefore described have beendesignated by numerals previously used, with the suiix a.

In this form of the invention, the bushing 18 has an internalrecess 19ior the reception of the enlargement 12n of the core 10, the bushing andthe core being permanently connected. The flange 4 of the carrier 3"L isconnected integrally to the bushing 18. The body 1EL has a closure 20,the closure being provided with openings 21.

The general operation ot the device depicted in Figure 4 is the same asthe opcration oi the device shown in Figure 1, so far as the adjustmentof the electrode is concerned.

Having thus described the invention, what is claimed is:

1. A spark plug comprising a body, a can rier in the body and includinga part having openings spaced apart, and a straight member insertableinto any of the openings, said member being provided at one end with ahead completely housed between said part of the carrier and the body ofthe plug, the

opposite end of said member projecting into the body to form anelectrode.

2. A spark plug comprising a body, a earrier in the body and including apart having 5 openings spaced apart, a member insertable into any of theopenings and having a head at one end, the opposite end of said memberprojecting into the body to form an electrode, said part of the carrierhaving;l a single elongated groove with which all oi the openingscommunicate, the groove receivingr the head when said member is mountedin any of the openings.

In testimony that I claim the foregoing as my own, I have heretoai'lixed my signature.

HARVEY S.. PRA' `T.

